Thursday, December 12, 2013
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Today, the winner of the $3 million 2014 Milner Prize (see candidates) will be announced in San Francisco along with five winners of the $3 million Milner-and-few-pals Award in Life Sciences (I hope that I remembered the official name of the honor exactly). One $3 million prize for a psychic (no kidding) will be decided in January. Watch the news.

His talk about the exotic methods to calculate the scattering amplitudes in gauge theory (and the whole symposium) was dedicated to David Kosower, Lance Dixon, and Zvi Bern who recently received the 2014 Sakurai Prize.

Aside from interesting comments on the internal structure of the amplitudes, the integrability that is being obscured by the local-and-unitary description based on Feynman diagrams, and the interesting creative confrontation between the S-matrix-like and Feynman-diagram-based techniques, Nima would say interesting things about the sociology of physics and especially the different personalities of physicists.

These sociological comments appear close to the beginning; and around 21:00.

To make the story short, even good physicists are divided to prophets and non-prophets. I think that Nima is using the word "ideologue" as a synononym for a "prophet". Kosower, Zvi, and Bern are also being praised for having been able to work on topics that were not really fashionable. Some authors of junk popular books use the word "seer" and it means pretty much the same thing, although at a more vulgar and obscene level.

A difference is that Nima views the "prophet" label as a negative one. These people are overpriced, he thinks, and they are often given credit for making vague prophesies that turn out to be right "in some sense" even though some degree of agreement is almost guaranteed to materialize and very different people have done the hard work to decide what is exactly true and what is not true and why.

Kosower, Bern, and Dixon are praised as the non-prophets by Nima; Nima himself degrades himself into a prophet. In fact, he is a serial ideologue who is ready to become an enthusiastic supporter of today's ideology while instantly abandoning yesterday's ideology. On the other hand, the really smart people don't need any ideology – they just adopt ideas from all sides and create something neat out of them, Nima explains. Needless to say, Nima is displaying some (cute but partially staged) modesty and apparent masochism by these comments; he is an excessively good worker who is also using ideas from all directions, regardless of the origin.

I would like to emphasize that this separation of the physics community wasn't invented by Nima Arkani-Hamed (or Lee Smolin). I've been aware of a similar one for 25 years – since my first reading of Albert Einstein's 1918 speech celebrating Max Planck's 60th birthday that was included in "Mein Weltbild", a book whose Czech translation I liked to re-read as a teenager.

In the temple of science are many mansions, and various indeed are they that dwell therein and the motives that have led them thither. Many take to science out of a joyful sense of superior intellectual power; science is their own special sport to which they look for vivid experience and the satisfaction of ambition; many others are to be found in the temple who have offered the products of their brains on this altar for purely utilitarian purposes. Were an angel of the Lord to come and drive all the people belonging to these two categories out of the temple, the assemblage would be seriously depleted, but there would still be some men, of both present and past times, left inside. Our Planck is one of them, and that is why we love him.

I am quite aware that we have just now light-heartedly expelled in imagination many excellent men who are largely, perhaps chiefly, responsible for the building of the temple of science; and in many cases our angel would find it a pretty ticklish job to decide. But of one thing I feel sure: if the types we have just expelled were the only types there were, the temple would never have come to be, any more than a forest can grow which consists of nothing but creepers. For these people any sphere of human activity will do, if it comes to a point; whether they become engineers, officers, tradesmen, or scientists depends on circumstances. Now let us have another look at those who have found favor with the angel. Most of them are somewhat odd, uncommunicative, solitary fellows, really less like each other, in spite of these common characteristics, than the hosts of the rejected. What has brought them to the temple? That is a difficult question and no single answer will cover it. To begin with, I believe with Schopenhauer that one of the strongest motives that leads men to art and science is escape from everyday life with its painful crudity and hopeless dreariness, from the fetters of one's own ever shifting desires. A finely tempered nature longs to escape from personal life into the world of objective perception and thought; this desire may be compared with the townsman's irresistible longing to escape from his noisy, cramped surroundings into the silence of high mountains, where the eye ranges freely through the still, pure air and fondly traces out the restful contours apparently built for eternity. With this negative motive there goes a positive one.

You see that it's not quite the same thing but it's related. Einstein divided the temple of science to profit-seekers (or utilitarians) and ego-builders (or athletes) on one side and monks (or missionaries) on the other side. Max Planck was included into the rare latter category by Einstein. Despite Einstein's stellar moral credentials in the public, I actually find it plausible today that Einstein himself might have been a representative of the former category as the Einstein and Eddington movie suggested. He might have been an utilitarian, not a monk (which I used to believe to be an accurate label for Einstein 25 years ago).

But let's gradually return to the modern separation to prophets and non-prophets. While the prophets are analogous to Einstein's monks when it comes to their spiritual motives, it is the non-prophets who may be closer to Einstein's description of the monks when it comes to the silence and modesty. So a bit paradoxical transformation of the two groups has taken place; it's the prophets (formerly monks) who are good at exciting emotions and P.R. these days and the engineer-like hard workers are the modest ones. ;-)

I don't want to make this discussion completely chaotic so let's return to Nima's modern separation of the two castes of physicists completely. Which group is "better"? Well, I think that both groups – and groups in between as well as completely different groups – are important for the health of science. Lots of detailed if not "microscopic" work has to be done for the big-picture or at least "macroscopic" skeleton to be robust. And the microscopic work may often grow to something grand.

On the other hand, if Nima were suggesting that the "ideological", big-picture thinking may be completely removed from science, I would strongly disagree. Even if we agree that science is not "entirely" about the big-picture questions only, it is "also" about them. The big-picture thinking is needed to be aware of the relative importance of different kinds of the microscopic work, too. It's needed for the bulk of researchers not to be caught in some minor technicalities while big questions and discoveries in different research directions remain neglected.

So the non-prophet researchers often end up doing many important results but this fact doesn't make their attitude superior because there are many non-prophet researchers who aren't that happy. In some sense, I do think that the importance of the research separated from the big picture is a matter of chance. (It may be non-PC these days but I still find it important to point out that I still consider Lance Dixon's work between 1985 and 1991 on orbifolds and related questions in string theory – including the monstrous moonshine – to be more important than all his later work on amplitudes combined. And I know some profound researchers who agree with me.) Moreover, the big-picture interpretation of some results is often a matter of a clear thinking. Someone doesn't see what some partial technical results actually mean, what are their (more) far-reaching implications, but someone else does see it and it's important to know it if it is true – or at least "somewhat vaguely true".

The really dangerous trap of the "ideological" approach to science – and Nima is obviously aware of it – is the ability of the ideological prejudices to remove one's impartiality. One may invent rationalizations for the decision to ignore some individual, "minor" results that go in an ideologically inconvenient direction and, as Nima says, everyone does it to a certain extent because it is a human thing to do so.

Well, first of all, I would say that it is not only human but to a large extent, it is right, rational, and scientific. Some principles – and even "somewhat vague prophesies" – are so powerful and important that it is right to dismiss some individual results contradicting a principle as "almost certainly wrong ones" and others as "potentially misinterpreted exceptions". In my opinion, it is important not to overlook the forest for the trees. A macroscopic perspective is often necessary.

On the other hand, the macroscopic reasoning and perspective is usually imperfect, at least a little bit imperfect, and it's important to realize its limitations and the inability of a philosophy to dictate the character of valid scientific results forever. A philosophy may have "worked" for years but it may still break down on a sunny day if not a cloudy day. Philosophies aren't guaranteed to work forever; their strength boils down to collective features of established (and ultimately empirically supported) scientific findings, too.

People are trying different strategies to approach questions, different degrees of confidence in the "literal" or "microscopic" thinking on one side or the "far-reaching" or "macroscopic" or "ideological" thinking on the other side. Some of them are sometimes more successful than others so the community of researchers may constantly update the weights and decide about a sensible role assigned to the philosophical vs literal thinking about the problems.

So I believe all kinds of thinking may turn out to be superior in different contexts and I would never cherish one of them only. It's important to preserve the scientific integrity, to work hard, and to realize that any belief is potentially fallible and falsifiable. Regardless of one's focus on big-picture arguments, principles, and philosophies, a sufficient amount of results may accumulate to convince someone that his or her previous beliefs were imperfect or downright wrong. It's wrong if someone's stubbornness is infinite; but it's also wrong if someone tries to eliminate the "inertia of beliefs" because this inertia has very good reasons to exist. Nima, with his promotion of conservatism in physics, would agree even though this comment seems to be in a tension with some other assertions he has made.

The anthropic controversy is an interesting playground to think about these ideological-vs-technical issues. The anthropic-vs-non-anthropic dilemma (perhaps equivalently, anthropic-vs-naturalness dilemma) has been something that Nima has considered spectacularly important in the recent decade. It's the ultimate crossroad of science for him. It made him excited and led him to write numerous papers – sort of on both sides of this aisle. It's good that ideologies may do some creative work.

But others, like myself, would never share this excitement. I think that neither the existing non-anthropic (or "natural") solutions nor the existing anthropic ones look like a satisfactory final answer to the questions that these paradigms are supposed to answer (especially why some small parameters in Nature are so small).

The existing anthropic explanations are largely vague, illogical, ill-defined, acausal, and unpredictive, among related vices. The existing natural explanations of all the small parameters either contradict some empirical data or fail to be really natural or are heavily non-unique, among related vices. In my opinion, that's why it is wrong to pretend that we have reduced the possibilities to a shortlist of two candidates. We don't have any two good candidates. The true answer to all these "anthropic" questions may very well be e.g. a mechanism that divides each hierarchy to numerous "minor hierarchies"; or it may be a solution that lies in between the anthropic one and the non-anthropic one or a solution that renders the question "is the anthropic principle right" meaningless or ambiguous (some nearly unimaginable hybrid). We just don't know. We don't have good "final models" which is exactly the situation in which one should stay open-minded.

But when it comes to the very ability of "scientific ideologies" to stimulate some work, I think it is a good force of Nature. Science is not only a competition between individual detailed technical hypotheses; it is a competition between "big paradigms" or "ideologies", too. It's important that the battle obeys the scientific rules and that no candidates are eliminated "a priori" (the "a posteriori" elimination, i.e. falsification, is right and essential, however). At the end, the ability of technical results to support or disfavor "ideologies" is one of the main reasons of their existence – and I think that this claim is especially true in research that has no applications because "big questions" are among the primary motivations of the pure scientific research.

An extra comment about some particular ideologies – the "amplituhedon" and the "spacetime is doomed". The amplituhedron work and the results that led to it are amazing mathematical insights but I don't really see how they support the "spacetime is doomed" ideology. I have already discussed this issue in the second part of the diaperhedron post.

The spacetime is doomed but the space in which the amplituhedron lives is some "auxiliary space" of a mathematical character that has no direct "physical" interpretation. In some sense, I believe that every interpretation that may be called "physical" must make some references to the spacetime, to the relative positioning of objects or events (although the modern descriptions often make the very character and shape of the spacetime highly non-unique etc.). Nima and Jaroslav don't really have a "replacement" for the physical concept of the spacetime which is why so far, their space must be viewed as an auxiliary space whose ultimate purpose is just to be a tool in the intermediate steps required to make valid propositions about the spacetime phenomena at the end.

I may be more explicit. I think that the conceptual role of the space hosting the amplituhedron isn't too different from the status of the moduli space of Riemann surfaces in string theory. It's some auxiliary space. Integrals over this space produce scattering amplitudes (although the technical details are very different).

In the 1980s, e.g. during the First Superstring Revolution, people would view the concepts of perturbative string theory – including the moduli spaces of Riemann surfaces – as the fundamental ones while spacetime was already reduced to a secondary emergent object. However, I think that this way of thinking was really "undone" by the Second Superstring Revolution in the 1990s that returned the physics to the spacetime, sort of. Objects associated with weakly coupled strings were downgraded to some effective description that is only useful in a corner of the stringy configuration space. The physical claims that were valid universally, even at strong coupling, had to be reconnected with the spacetime once again.

In this sense, I believe that Nima's ideology is trying to undo the Second Superstring Revolution again and upgrade a particular auxiliary structure – analogous to those in a weakly coupled limit of string theory – to the Master. But I think that he doesn't have the evidence that these mathematical structures should be the new Master. So even his amplituhedron findings may have been done due to Nima's excitement about the "spacetime is doomed" paradigm, I think that the final amplituhedron findings don't really bring us any new evidence in favor of the "spacetime is doomed" reasoning.

If I am right, this is not the first time in the history when important findings were stimulated by some ideology that finally turned out to be very problematic or wrong, of course. For example, Einstein's search for a new theory of gravity was importantly stimulated by Mach's principle but the final result, the general theory of relativity, doesn't really endorse Mach's principle. Ideologies may play both destructive and constructive roles but it's important to separate the science from personal emotions and histories. Someone's excitement about an ideology isn't a proof of this ideology even if this someone finds something important in science!

Ah, the amplituhedron findings. If only I had the brain of a Witten for a day or two to grok them. All the same, I'm sure you're right Lubos that wrong mental models can still lead to discovery of breakthrough results which in no way prove those models. Fascinating stuff.

This is a very nice inspiring article and yeah, a new Nima talk ... :-)

I think good prophets need to have a good physics intuition, which can only (almost exclusively) be acquired from having a good broad and deep knowledge about all parts of (theoretical) physics, needed to see deep important relationships and the big picture correctly. It does not fall out of the blue when lying lazy under a tree or bubbling nonsense in a youtube video while lying flat on your back on the grass, as some of the worst crackpots think ... ;-).

To really confirm the prophecies and big pictures, a lot of hard work (and often help from mathematicians) is needed, which can be done by other people who did not have the original broad idea too.

Anyway, I think the most important thing for good physicists of both types is to seriously love what they are doing, either calmly and silently of more visibly and intoxicating others, depending on the individual temperament.

A hopefully not too bold comment:

I like both types of good physicists, Nima who is always very enthusiastic and makes me feel very excited when watching his talks, and people who seem to be very calm, nice, but immensely knowledgable too, such as Qmechanic or Cumrun Vafa. So my guess is that Qmechanic is not Nima ... ;-)

(Lumo, please truncate the last paragraph if you think it is too inappropriate or bold, I can not edit my comments here when not being able to log in ...)

Belbin Team Role Inventory is another name for Nima's observation, which claims there are nine behavioural traits within any organisation:

http://en.wikipedia.org/wiki/Team_Role_Inventories

People display a combination of all nine with some emphasised more than the others. I'd say Nima comes across strongly as a co-ordinator, shaper, team-worker; with Kosower, Bern, and Dixon perhaps more specialists and finishers.

Lubos writes: "Regardless of one's focus on big-picture arguments, principles, and philosophies, a sufficient amount of results may accumulate to convince someone that his or her previous beliefs were imperfect or downright wrong."

Too bad that doesn't happen more often in the field of political economy.

Michael Hudson is one of great giants among political economists, Lukelea. He is every bit as ballsy as he is brainy. Hudson is second to none when it comes to making an air-tight case against neoliberal imperialism, thus making him public enemy numero uno to all the plutocratic power elites living off the loot from our FIRE-friendly economy. They vehemently despise him for consistently arguing the inarguable: in order to have a strong economy with staying power, labor and production must take priority over capital and finance.

It's, of course, no surprise that the the silliest and the most paranoid of the regular contributor's to this blog is a follower of one of the world's cynical purveyors of paranoid conspiracy theories:

"In the 1970s the Cold War metamorphosed into détente as America and Russia formed trade ties, capped by U.S. grain sales. Russia’s opening to the West led to glasnost and perestroika in 1986, and five years later the USSR was dissolved. In one of the greatest economic about-faces in history, Russia was persuaded to assign its mineral wealth, land and enterprises to insiders drawn mainly from the ranks of the old Soviet nomenklatura and mafiya. When the dust had cleared, Russia discovered that its industrial, agricultural and military production had been dismantled. America had ringed it with military bases from Central Asia to outer space, and was using the flight capital of its kleptocrats to buy out what remained of the nation’s natural resources and other assets."

Of course, according to this view of the world, this:

In the 1970s the Cold War metamorphosed into détente as America and Russia formed trade ties, capped by U.S. grain sales. Russia’s opening to the West led to glasnost and perestroika in 1986, and five years later the USSR was dissolved. In one of the greatest economic about-faces in history, Russia was persuaded to assign its mineral wealth, land and enterprises to insiders drawn mainly from the ranks of the old Soviet nomenklatura and mafiya. When the dust had cleared, Russia discovered that its industrial, agricultural and military production had been dismantled. America had ringed it with military bases from Central Asia to outer space, and was using the flight capital of its kleptocrats to buy out what remained of the nation’s natural resources and other assets."

The difference between cynical scum like Hudson and his idiot followers like Cynthia is that the former is very well rewarded for peddling his garbage. Idiots like Cynthia, on the other hand, will readily believe that this:

In the 1970s the Cold War metamorphosed into détente as America and Russia formed trade ties, capped by U.S. grain sales. Russia’s opening to the West led to glasnost and perestroika in 1986, and five years later the USSR was dissolved. In one of the greatest economic about-faces in history, Russia was persuaded to assign its mineral wealth, land and enterprises to insiders drawn mainly from the ranks of the old Soviet nomenklatura and mafiya. When the dust had cleared, Russia discovered that its industrial, agricultural and military production had been dismantled. America had ringed it with military bases from Central Asia to outer space, and was using the flight capital of its kleptocrats to buy out what remained of the nation’s natural resources and other assets."

The difference between cynical scum like Hudson and idiots like Cynthia is that the former is well rewarded for the garbage he peddles world over, although if what he claims was true even in a small degree, he would long have suffered the fate of the late Jang Song-thaek. Cynthia, on the other hand, will readily believe that this American financial interests and “neo-liberal economists” are behind these events too:

Michael Hudson’s big theme, as I understand it, is that nobody took Keynes seriously and “euthanized the rentier.” Because of this, the rentier has pursued capital gains through blowing inflationary asset and commodity bubbles, which has imposed such high additional costs on the Real Economy that it has completely sucked out demand. This state of affairs has been allowed to continue even after the obvious salutary lesson of the Great Depression. Now the failure to learn a lesson from allowing this pursuit has given us once again another Great Recession to stagnate in. In simple terms, our problem is we allow two types of capitalism to run side by side: Real Economy Capitalism and Cannibal Capitalism. Real Economy Capitalism provides income through profits, while Cannibal Capitalism seeks income through capital gains based debt and price inflation, which has the negative effect of devouring demand in the Real Economy.

Yes, that is his Sarajevo, i.e. his pretext. He is also well aware that the only to “euthanized the rentier”, as you put it so nicely, is the way Lenin and Stalin “euthanized the kulak”. All his writings, just like yours, show a high degree of fondness of anti-Western totalitarian regimes, which are, according to his and (also yours) the only ones not in the pocket of the American financial interests. According to this view, there was nothing wrong with life in the USSR or any of the puppet state except for the naïve trust of the population in fake Western ideas of economic and personal freedom. Once these naïve fools of the former communist camp got conned by the “neo-liberals” all their so called “wealth” was stolen and they have been reduced to abject misery, which you can see by visiting Prague, Warsaw or even Moscow.

Comrade Ligachov would have loved him but I think it is Michael Hudson together with all his followers who should be euthanized before they euthanize the rest of us.

Holy shit what nonsense. Nobody took Keynes seriously? Keynesian nonthink dominated Academic "thought" in economics, and political policy, for the entire period from the 1950's till the 1980's. It's still a major, if not necessarily dominant, strain of "thought" in academic "economics" and has been applied off and on recent decades. I don't have to listen to anything else someone says after that, they are clearly a completely ignorant moron.

I like the indroductory overview about what the amplituhedron business really is about using not just words. But of course, to really understand it in detail one would have to dig much deeper and be smarter than me ... :-D

But it somehow picks me that they want to generalize this approach to make if work for other things than N=4 SYM, this makes me very curious ...